Drop feed mechanism for sewing machines



April 20, 1948. G. R. WAINWRIGHT DROP FEED MECHANISM FOR SEWING MACHINES Filed Sept. 15,1945 2 Sheets-Sheet 1 v A IIIIIA'IIIIIII INVENTOR. 65020: A? WA/m/aflr 4 We2 4 2gp AIVWIEY Ap 20, 1948. cs. R. WAIN WRIGHT DROP FEED MECHANISM FOR SEWING MACHINES V I Filed Sept. 15, 1945 21 Sheets-Sheet 2 tram- A? latented Apr. 20, 1948 DROP FEED MECHANISM FOR- SEWING MACHINES George R. Wainwright, Glendale, Califi, assignor, by mesne assignments, to William H. Maxwell,

Los Angeles, Calif.

Application September 15, 1945, Serial No. 616,554

This invention relates to sewing machines and relates more particularly to a drop feed mechaniSm for sewing machines. An object of my invention is to provide simple, practicaland efficient means for quickly and easily disengaging the feed dog of a sewing machine for the purpose of affording "manual control of the material being stitched by the machine.

When sewing the seams of a garment or the like, greater seam strength is obtained if the end of the seam is stitched over several times.

.Since the feed dog of the conventional sewing of the material being stitched.

Another object of my invention is to provide a drop feed mechanism for sewing machines which can be operated without lifting or otherwise disturbing the head of the machine.

Another object of my invention is to provide means for uncoupling or disconnecting the feed dog operating mechanism of a sewing machine by means of a control carried on the outside of the sewing machine head.

Another object of my invention is to provide a simple finger tip control carried on the outside of a sewing machine head for quickly and easily controlling the feed and non-feed condition of a sewing machine feed dog.

A further object of my invention is to provide simple, eflicient and positive means for efiecting coupling or uncoupling of the feed dog operating mechanism of a sewing machine, which means can be readily, incorporated or embodied in existing sewing machines.

The various objects and features of my invention will be fully understood from the followin detailed description of a typical'preferred form and application of the invention, throughout which description reference is made to the accompanying drawings, in which:

Fig. 1 is a bottom plan view illustrating the general arrangement of parts of a sewing machine head embodying my invention; 1 V

Fig. 2 is a cross-sectional view thereof taken 9 Claims. (Cl. 112-203) substantially as indicated by line 22 on Fig. 1;

Fig. 3 is a vertical sectional view taken substantially as indicated by line 33 on Fig. 1 showing the relationship of the feed dog to the pressure foot.

Fig, 4 is an enlarged fragmentary detail side view, partly in section, of a drop feed mechanism embodying my invention;

Fig. 5 is a fragmentary detail vertical crosssectional view taken in the direction of line 55 on Fig. 4, certain parts being shown in section while others are shown in elevation to illustrate the relationship of parts;

Fig. 6 is a view taken on the line 66 of Fig. l;

Fig. 7 is a fragmentary detail view as seen in the direction of the arrow 1 of Fig. 4; and

Fig. 8 is a fragmentary view as seen in the direction of the arrow 8 of Fig. 5.

"nism 20, etc.

In the drawings I have illustrated a preferred embodiment of my invention as applied to a typical sewing machine. I wish it to be understood, however, that the particular design of drop feed mechanism which I show can be varied in many ways within the broad concepts of my invention and that said mechanism can be applied to various types of sewing machines.

In the embodiment of the invention which is illustrated, the drop feed mechanism may be said to comprisea. sewing machine head It] having a typical throat plate ll, presser foot l2 and reciprocating needle bar l3. A feed dog It operates through an opening IS in the throat plate II and cooperates with the presser foot l2 to feed material in intermittent synchronous relation to the movement of the needle bar IS. A mechanism l6, of generally conventional form, imparts horizontal or feed movement to the feed dog I4 and a mechanism II, also of conventional form, imparts vertical movement to the feed dog l4 synchronously with the horizontal movement of said feed dog whereby said'feed dog has a gyrating movement to intermittently feed material being stitched. A means I8 is provided for uncoupling or disconnecting the mechanism I! to stop the vertical movement of the feed dog l4 and to retain the latter in depressed or lowered position with respect to the throat plate I I and a means I9 is carried on the outside of the head ill for operating the means Ill. The machine also includes various other details, parts and means such as a shuttle operating mecha- The sewing machine head It is of conven tional form and comprises a bed plate 2|, a hollow column 22 for thearm of the machine, and

selective engagement in detent seats 13 and 14 in the rear face of the boss 68. On the outer face of the escutcheon 65 and in relation to the detent seats 13 and 14, I provide suitable indicia comprising the words IN and OUT and readable in connection with an index portionl of the handle 63. v I

In the drawings and particularly in-Fig. 4, I have shown the machine in-normal operating condition with the feed in, with the detent 12 in the detent seat '73 and the handle index 15 indicating this feed in condition of the machine. When the operator desires to throw out or drop the feed, he merely flips the handle 63 so the index 15 points to the word Out on the escutcheon and the detent 1-2 finds the detent recess 14. This movement of the handle 63 will tilt the latch 49 against the action of the spring 60 to withdraw the pin 58 from the notch 42. The rockshaft 33, now being freed from oscillation by the link 35, is rocked by the spring 55 to bring the lever arm 36 to a low position as determined by the stop pin 58 and its engaging lug 51,. The lever arm 36, in its low position, holds the feed dog I4 depressed out of engagement with the material being sewn. The detent 12 will retain the parts in this condition until it is desired to throw the feed in again. By flipping the handle 63 back to its original position pointing to the word In, the latch 49 is freed so that its spring 60 becomes efiective to urge the pin 52 into coupling engagement in the notch 42. Since the lever arm 34 is in continuous oscillation, whether the feed is in or out, the latch pin 52 may seek the notch 42 when out of registry. In this case, the pin will come to rest momentarily upon the upper curved edge Hi of the extension 4| and as registry between the notch and pin is obtained, the latter will slip nicely into place. Also, since it is desired to operate the drop feed mechanism during any portion of the cycle of operation of the sewing machine, the latch arm 50 is made sufficiently wide to at all times be engageable by the control lever end 10.

Having described only a typical preferred form and application of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art and fall within the scope of the following claims.

Having described my invention, I claim:

1. A drop feed mechanism for sewing machines or the like including, a feed dog, means including a rock-shaft and a notched lever-arm thereon for normally imparting vertical reciprocatory movement to said feed dog, means for separably coupling said rock-shaft and said lever-arm including a latch pivotally carried by said rockshaft and having latching engagement with the notch of said lever-arm, means for manually operating said latter means, and means operable upon uncoupling of said rook-shaft and leverarm for holding said feed dog in non-feeding position.

2. A drop feed mechanism for sewing machines or the like including, a feed dog, means including a rock-shaft and a lever-arm thereon for normally imparting vertical reciprocatory movement to said feed dog, means for separably coupling said rock-shaft and said lever-arm including a latch pivotally carried by said rock-shaft and having latching engagement with said lever-arm, means for manually operating said latch including a pivotally mounted handle accessible from the outside of said sewing machine and detent means for maintaining said latching means in selected operating position, and means operable upon uncoupling of said rock-shaft and leverarm for holding said feed dog in non-feeding position.

3. A drop feed mechanism for sewing machines or the like including, a feed dog, means for moving said feed dog in normal operation and comprising mechanism for imparting reciprocating horizontal movement to the feed dog and mechanism for imparting synchronous reciprocating vertical movement to said feed dog, said latter means including a rock-shaft and a notched lever-arm freely mounted directly thereon, means for separably coupling said rock-shaft and said lever arm including a latch pivotally carried by said rock-shaft and having spaced arms one having latching engagement with the notch of said lever-arm, means for manually operating said latter means including a pivoted member having a handle accessible from the outside of said sewing machine and having a lever arm extending between the arms of the latch and detent means for maintaining said latch in selected operating position, and means operable upon uncoupling of said rock-shaft and lever-arm for maintaining said feed dog in depressed non-feeding condition during continued operation of the mechanism which imparts the horizontal movement to the feed dog.

4. A drop feed mechanism for sewing machines or the like including, a feed dog, means for moving said feed dog in normal operation and comprising mechanism for imparting reciprocating horizontal movement to the feed dog and mechanism for imparting synchronous reciprocating vertical movement to said feed dog, said latter means including a rock-shaft and a lever-arm surrounding and freely pivoted thereon, means for separably coupling said rock-shaft and said lever-arm including a latch pivotally carried by the shaft and engageable with the lever arm, means operable upon uncoupling of said rockshait and lever-arm for maintaining said feed dog in depressed non-feeding condition during continued operation of the mechanism which imparts the horizontal movement to the feed dog, and means normally yieldingly holding the latch in position to cooperatively engage the lever-arm, said latter means including a tension member normally urging the latch toward the lever arm.

5. In a sewing machine or the like, a feed dog, mechanism for imparting vertical reciprocating movement to said feed dog and including a rockshaft connected with the feed dog and means for oscillating the rock-shaft including ,a leverarm freely mounted on said rock-shaft, a latch carried by the rock-shaft, means normally engaging the latch and the lever-arm for the mentioned oscillation of the rock-shaft and comprising a tension member engaged with the latch, manual means for disengaging the latch and the lever-arm, and means operable upon said disengagement for positioning and maintaining the feed dog in non-feeding condition.

6. In a sewing machine or the like, a feed dog, mechanism for imparting vertical reciprocating movement to said feed dog and comprising a rock-shaft connected with the feed dog and means for oscillating the rock-shaft including a lever-arm freely mounted on said rock-shaft, a latch carried by the rock-shaft, means normally engaging the latch and. the lever-armfor the mentioned oscillation; of the; rock-shaft; manual? meansfor; disengaging the latch and :the. lever: arm;v and means i operable; upon. said-.1disengage1 of. the rock-shaft in one direction; and al'tension member around the rock-shaft: and; connected v to the arm andzto theabutment'; for rotating'the;

rock-shaft to abut the: arm; andxthe. abutment.

'7.v In a. sewing;.machine ortherlikeg a rockshaft; a. driven freely: mounted levenarm sur-: rounding said. rockeshaft, andghaving a notchi therein, means for vseparaloly Vcouplingithe rock: sh'aftrand the lever-arm including amemben fixed on the shaft adjacent the leverearmr and having apair of spacedlears, a iatchlpivotallymount.- ed between said ears and. engageable. with the notch, and tension meansv normally; positioning the latch to engage the notchof the lever-arm;

8. In a sewing machine: or the 1ike,.ia,' rocke shaft, a driven freely mounted lever-armzon saidl rock-shaft and having a notchtherein,.me ans for separably coupling thev rockeshaft. and thelever-arm comprising a memberadjacent the lever-arm, a. pivoted:latch carried by saidmember, tension means; normally couplingthealatch Withi the: notch, of, the. lever-arm, and manuals meanafor tilting the latch against, the force ofv thetension meansytmuncouple the .latchand the? notchedtlever-arm;

9. In; ,a sewingmachine and the like, a rockshaft; a, driven-freely mounted lever-armonsaid: rock-shaft and having a notch therein; means for separably coupling the rock-shaft, and the lever-arm comprising a. member. adjacent the leverearm; aw pivoted jlatch: carried said member, tension means: normally coupling the latch.

Withthe notcht of the. lever-arm manuals means for; tilting/the latch against the force of the tension means. to uncouple -the-latch and the notchedlever-arm, and means;v operable upon-uncoupling of the latch and lever-arm. to maintain thee rook-shaft stationary during continued driven movement of the lever-arm;

GEORGE R. WAINWRIGH'I'.

REFERENCES CITED The following references are of IECOITdLiIIZ the file. of: this patent:

FOREIGN PATENTS Numbera. Country Date 298;!)49 Great Britain g Oct. 4-, 1928 513,908 Germany-,n nu u Dec; 4, 1930' 

